RE: wing mfg p-40 . to electric
I have a power 32 from value hobbies, a 60 amp controller without BEC, and a 4S battery in a 40 size stick. This setup produces 740 watts and a 45 amp draw with a 12X6 prop. My stick weighs between 5 and 6 lbs, I did not weigh it yet. If you use the rule of thumb of 100 watts per lb for a sport plane this should fly your 6lb P40. I also use a 6 volt receiver battery as I do not like to fly the bigger models with a BEC. I prefer the margin of safety of not having the radio and servo on the flight battery.